Installing Kopano Core Community Edition on Debian 9 Problems

Hello,
I am happy user of Zarafa Server that serves me for years now. I wanted to test the new Kopano System in its Community Edition on a fresh installed Debian 9 VM. Unfortunately this seems to be a little bit hard.

Before installing Kopano, I installed LAMP (with mariadb-server not mysql-server). After that I downloaded the the latest packages of Kopano for Debian 9 amd64. After installing the .deb packages from the core archive and resoving missing dependencies with

apt-get -f install

I still have problems with libjs-backbone package. So I installed it manually with apt-get and reinstalled the *,deb packages from the core archive without any problems. When I restart the VM now, I can’t login anymore to the kopano user account?